Putting Foam in your boat?

[MountainManMyke]

Hey guys, I am just redoing a 1976 princecraft fiberglass tri hull 15ft. I have redone the stringers and I have all my pieces to my plywood floor all cut. The boat was not in good condition when I received it so I am unsure if there was foam. Would any buddy know if there was foam under the floor? If so, what kind and where would I get it? Thanks guys

 

[dkillianjr]

Re: Putting Foam in your boat?

I really can't tell you if there was foam under the floor or not. But if you end up picking some up www.uscomposites.com has it. Thats where I plan on getting mine.



Dave

 

[Bob_VT]

Re: Putting Foam in your boat?

If it was built to the BIA or USCG specs ......yes it had foam (or was required to have it) and yes, most of us agree you should replace it for safety.

The is a nice write up on foam here http://forums.iboats.com/showthread.php?t=288451

 

[proshadetree]

Re: Putting Foam in your boat?

If you have read much you will get the foam argument I hate it and will not use it unless I have to

 

[idonthaveaname]

Re: Putting Foam in your boat?

Here's the dealio as far as I am concerned. It's a 15 foot boat...mines a 14 foot. There was foam in it when I started the rebuild. I have owned a few jon boats from 12 to 17 foot--none have had foam so replacing foam in one of these small boats doesn't really make a lot of sense. CC requirement aside, it's probably a good idea however to have at least enough foam to keep it afloat for safety and salvage.

 

[zach103]

Re: Putting Foam in your boat?

i have a 17 ft and a 14ft. both have foam from us composites.. you just do two even liquid amounts mix and pour.. than what i did was take a hand saw and just lay it on top of the stringers and wa la! oh and make sure its as flat as you can get it when you pour.. but for 70 or so dollars its worth it.

 

[MountainManMyke]

Re: Putting Foam in your boat?

How would I apply the foam? just around the perimeter good enough? There's alot of space up front for foam but towards the back of the boat not much room because of my drainage. Thanks guys

 

[mytquinn]

Re: Putting Foam in your boat?

Where to put the foam? Everywhere under your deck that you can.

I would (and did in mine) lay down some plastic sheeting first. The foam will not stick to it. Also wrap some plywood in the plastic as well to serve as the top of your pour. Then mix your foam, pour it into your plastic lined void, and cap it with your plastic lined plywood. It will only take a couple of minutes and your foam will be solid. Mix a batch first to see how long it takes. After your pour is done, remove the plywood top (I just sat on mine while it cured. Doesn't take long.) Now you can remove the block of foam you just poured, if it's not wedge locked in place. Check that before you pour! Now you can carve your drain channels into the bottom of your foam. You can also encapsulate it in epoxy for added protection from absorbing water. I don't think you really need to worry about it if you allow for drainage. Most foam is wet because the water has no where to go. If you allow for drainage, then you should be good.
Also, +1 on US Composites. Shipped all the way to Colorado, and still the cheapest solution around. Customer service was also very good. Products very good as well.

 

[ezmobee]

Re: Putting Foam in your boat?

Whether to foam it or not is your choice. Personally, should the unthinkable happen, I'd rather have this http://www.ohiogamefishing.com/community/attachment.php?attachmentid=35283&stc=1&d=1280968871 to hold onto while waiting for help to arrive than treading water.

 

[NSBCraig]

Re: Putting Foam in your boat?

I thought you were NOT supposed to cut it like Zack said he did.

That you didn't want to break the surface.

Not sure look into it before you do.

(No foam in my boat)

 

[idonthaveaname]

Re: Putting Foam in your boat?

IMHO Closed cell foam, by virtue of it being closed cell, does not absorb water. Encapsulating closed cell foam into plastic could create problems in the future otherwise, manufacturers would do this in the first place. What occurs is the plastic wrap leaves pockets within the installation allowing water to sit and condensate. This leads to rot, mildew, and a host of problems. It is best to create drain tunnels through the use of PVC so water can drain and those channels can be created prior to foam installation. Your closed cell foam should come into direct contact with your hull.

 

[Bondo]

Re: Putting Foam in your boat?

IMHO Closed cell foam, by virtue of it being closed cell, does not absorb water.

Ayuh,... My guess is, you haven't spent any time removing Tons of waterlogged closed cell foam outa old boats before...

Closed cell foam, don't stay closed cell for very long...

The Best alternative I've seen, is using foam Board insulation...
It to is Closed cell, but the mere fact that is in Board form, allows proper DRAINAGE...

Foam, or No Foam,..... Drainage is the key to longevity...

 

[idonthaveaname]

Re: Putting Foam in your boat?

Ayuh,... My guess is, you haven't spent any time removing Tons of waterlogged closed cell foam outa old boats before

Oh yeah...done plenty of that. I agree it won't stay closed forever, but with proper sealing and proper drainage, it should stay dry for a long time. My Whaler was over 30 years old and the foam was as dry as the day it was bought. Most of the problems I have seen with old boats and squishy foam is there are a lot of other problems. Even wrapped in plastic, or filled with pool noodles, you'll have issues with mildew and rot. When I opened up my latest project, the "foam" under the deck was a flippin mess, then again, 80% of the floor was rotted and leaking. This time, like the factory did, I will pour the foam directly onto the hull.

Each has their own method I suppose.

 

[Hoggar]

Re: Putting Foam in your boat?

Just to widen the question here...

What are the pros and cons of 4lb VS 2lb foam?
Is that the weight of the foam after curing or the weight it will displace?

I am doing a cathedral hull which is similar to a trihull and will be replacing the foam in mine.

 

[Bondo]

Re: Putting Foam in your boat?

What are the pros and cons of 4lb VS 2lb foam?
Is that the weight of the foam after curing or the weight it will displace?

Ayuh,... It's what it weighs, per cubic foot, after cured...
2lb is less dense than the 4lb...

 

[MountainManMyke]

Re: Putting Foam in your boat?

So would it be okay to mold the foam to my hull, remove it and then notch or drill holes for drainage? Or does it premenently bond to the hull where I would have to use pcv pipes before I pour the foam? Also, should I be safe with ordering 10 cubic feet of the 2lbs density foam for my 15 ft boat? thanks

 

[idonthaveaname]

Re: Putting Foam in your boat?

Personally, my preference would be to lay the pipe for drainage so I could direct the water. Next, I'd pour in foam to cover everything. That's just my opinion and others will have theirs which is what is great about this forum. The point, I think, is to be creative as to where you place the foam. For example, if you can install foam above the water line you'd be better off, but everyone wants to stick it under the deck where water collects. If one could fill all the nooks and crannies on the cap rather than the deck, the foam would stay dryer for longer, and since many of us pull the cap when refurbishing, we should be able to figure out how to get the foam in there. As far as using the boat for a flotation device, that's old thinking at work. In the past no one wanted to wear a bulky PFD, but today they are small, self inflating, and fasten on your waist. On the other side, the only solid reason one would want boat buoyancy is salvage and even then, we aren't talking about ALL boats having foam. The CC requirement for builders is what? 17 or 20 something feet? What about a 30 footer? Do you think they are going to float? Maybe they shoulda had foam on the Titanic. ;-)

 

[tboydva]

Re: Putting Foam in your boat?

I can offer a suggestion (worked well for me). Take a section of lager diameter PVC pipe (3-4") and "rip" it (lengthwise) to make a semi-circle. Drill it full of holes (for drainage). Lay it down along the centerline of the boat, then use paper mache to cover it and "fasten" it to the centerline. Paper mache turns to mush in water - but not in organic solvent(s) (like urethane foam). After your foam dries, you can shoot water into the pipe - or just leave it and let it dissolve over time. This worked perfectly on my restore with no waterlogged foam to date. I agree with the other posts - if you have adequate drainage, you won't have waterlogged foam. Good luck!

 

[MountainManMyke]

Re: Putting Foam in your boat?

I have squared supports that sort of looks like a half box running the length of most of my boat. its a piece of plywood 4 inches wide and 87 inches long running horizontal and then a verticle piece thats 4 inches wide and 87 inches long that are fiberglasses together and then fiberglassed to my floor. I was thinking I can just fill up these channels with foam because they are hollow anyways and it will be above the water line. I think that should be sufficient. Let me know what you guys think. Thank you

 

[Yacht Dr.]

Re: Putting Foam in your boat?

Hello MountanMan..

My opinion would be if it didnt have foam where you want to put foam..Dont foam

Unless you put enough foam in your boat to keep it from sinking then its worthless and IMO a waste of money/time. It may be possible that your doing more harm then good in the long.

So dont foam unless you have foam for floatation or part of the structural integrity of the boat.

YD.

PS. I dont recall you saying you actually had foam in your boat..just hypothetical ? Got Pics ?